Mounting and protecting device for cathode-ray tubes



July 3 l95l R. A. FlscH v 2,559,353

MOUNTING AND PROTECTING DEVICE FOR CATHODE-RAY TUBES Filed July 25, 1950 2 Sheets-Sheet 1 July 3, 1951 R. A. FlscH MOUNTING AND PROTECTING DEVICE FOR CATHODE-RAY TUBES Filed July 25, 1950 2 Sheets-Sheet 2 Patented July 3, 1951 UN :ITE D STATES PATENT OFFICE MOUNTING AND 'PROTECTING'DEVICE' FOR CATHODE-RAY TUBES Richard A. Fisch, Kew Gardens,.N. Y.

Application July 25, 1950, Serial No. 175,677

3 Claims. 1 This invention relates to a dust proof mounting and protecting ring for a flanged type of metal backed cathode ray tube.

An object of this invention is to provide av mounting ring for a cathode ray tube which simultaneously acts as an insulating device and which is adapted to carry a mask and a flat protective glass plate.

An object of this invention is to provide a mounting ring for a cathode ray tube which simultaneously acts as an insulating device and formed is located at one side of the ring and isl continuous and adapted to receive and straddle the exterior peripheral flange adjacent the lens or screen of the television or cathode ray tube. Another continuous'inter'ior groove formed by vthe flanges at-the opposite side of the ring isadapted to receive a protecting transparent plate. Be-

tween the twoA continuous grooves is a third' groove which may be continuous or discontinuous and which is adapted to receive a mask' for the screen. It is desirable to space the inter-v mediateA groove so that the mask does not actually touch the screen of the television tube.

The anges which form the groove that holds the protective transparent plate are made continuous so as to form a dustproof seal between the outer atmosphere and the space between the transparent plate and the screen or lens of the television tube. These flanges may be parallel to the flanges which are adapted to straddle the ange of the television tube or the two pairs of anges might be at a slight angle to each other so that an inserted protecting plate will slope slightly away from the plane of the lens of the television tube when the ring and protecting plate are tted in a television set. When the outer protecting plate slopes away from the plane of the lens of the cathode ray tube of a television set, the plate tends to deflect reected light` away from the eyes of the viewer and reduce Ythe interference o'f the reflected light with theA televised image.

The protective Vtransparent plate may be laminated glass, case hardened` glass or transparent plastic material such as methyl methacrylate resin. One vadvantage to the present invention is that the sleevel with the protective 2'- glass plate andmask may be ,placed on the cathode ray tube-beforeit is assembled into the tele'- vision set. not explode very often, they are under a high vacuum and when they do explode glass is thrown in many directions and dangerous injuries to life and property are apt tooc'cur. There is also a danger where there are numerous tubes about that a rst explosion will start a chain reaction of similar explosions since the ying glass particlestogether with the flow of `air which occurs when a rst explosion takes place are both likely to upset the equilibrium of other adjacent tubes. Another advantage of the construction is that it makes it possible to employ a iiat protecting plate.

The novel vfeatures characteristic of this invention arel set forth with particularity in the appended claims. The invention itself, however,

both as to its organization Iand its method ofv g operation, together with additional objects and advantages thereof, will best be understood from the following description of specic embodiments when read in connect-ion with the accompanyingA drawings in which:

vFigure 1 is a cross sectional view of a device made according to the present invention.

Figure 2 is a View similar to Figure 1 of a modified form of the device and taken on line 2 2 of Figure 3.

Figure 3 is a front cross sectional view of the device'taken on line 3 3 of Figure 2.

Figure 4 is a detail -view showingv how the ends of the ring are tted together.

'Figure 5 is a view illustrating how the ring of Figure 1l secures the'cathode ray tube to a television set.

When metal backed television tubes (shown diagrammatically at I0 in Figure 11) the metall' backing contains a flanged` portion H at the end thereof adapted to form a seat for the lens of thev tube, the lens being located at the area of the curved dot-dash line I2. Sincer the metal backing is under a' high voltage and since the lens must be visible, some means is necessary to insulate ilangedV area ll thereof to prevent persons, etc., from -being shocked by coming too close to the highly charged metal backing. The ring device 20 of the present invention insulates the front area ofthe tube-which is the only part that is exposed in a completed television set and' in addition vthe ring has other features Whichwillnow'be described inA detail.

The ring20 has two interior angesZI, 22 that extend all the way'aroundthe-ring andl form the Although such television tubes do' 3 groove 21 therebetween adapted to straddle the flange of the tube |0. The flange 2| is somewhat longer than the ange 22 and in addition contains the alternate ridges 24, 24 and valleys 23, 23. The valleys 23 and ridges 24 are added so as to give at least two inches of leakage path between the point where the tip of the flange 28 touches the metal backing and the tip of the external flange which may contact other parts of the set or cabinet. Opposite the internal groove 21 is the external groove 29 formed between the continuous exterior flanges 25, 26. This external groove 29 is adapted to hold the cable or cord which is tightened about the groove 29 to securely hold the ring 25 with its ends (Figure 4) together upon the flange of the tube I0. Y

The top part of the tube when it is mounted in a set would ordinarily be that part at the left hand side of Figure 1. The diverging peripheral flange 30, 3| extends outwardly from the base of the internal flange 22, the part 3|) vbeing at the top of the ring ,and the part 3| at the bottom thereof. About midway of the top portion 30 are the pair of internal flanges 3|, 32. Also the pair of flanges 33, 34 is located at one side of the ring and a similar pair 35 (only one shows in Figure 3) is located at the opposite side. These flanges are adapted to hold rim 52 of the mask 5|. The mask 5| is suitably formed to cut off a large part of .the distortion areas of the top, bottom and sides of the tube and furnish a rectangular viewing opening 53. One advantage in incorporating the mask 5| in the insulating ring is that by this construction it is possible to include a mask which is metallized,r the insulation material of the ring protecting the mask from the highly charged tube elements. In the construction shown in Figure 1, the lower part of the mask 5| is supported between flange 35 and the narrow flange 4| which served to separate the Vrim 52 of the mask v5| from the lower edge of the protecting plate 54.

This protecting plate 54 is held in tilted position with respect to theV lens I2 of the cathode ray tube by the pair of internal flanges 4|, 42

which are continuous with respect to the ring.v

These A.flanges 4|, 42 are substantially equally spaced relative to each other but instead of being equally spaced from the flange 22 gradually approach the flange 22 from the top 30 of the ring to the bottom 37| thereof. Therefore, the transparent plate 54 tilts downwardlywith respect to the plane of the lens |2 when the ring assembly is xed on a cathode ray tube. The interiorV flanges 4|, 42 are made continuous in order to furnish an air tight space between the flange of the-television tube and the Vtransparent plate 54. Since vthe lens l2 of the tube tends to collect an electric charge, dust particles from the air tend to precipitateupon the surface thereof. This destroys the visibility of the image causing the lens |2 to appear cloudy or dark. By making the area'between the lens |2 and the transparent plate 54 dust-proof, the continuous Vaccumulation of dust on the lens |2 isV shows a modified'form'of ring 20" 4 the substantal mirror images of the corresponding top flanges 3|, 32 and, the flange 4| which is to hold the inside edge of the transparent plate 54 is of uniform thickness and is uniformly spaced from the flange 22.

As shown in Figures 3 and 4 the ring 20 or 20 is an open one (prior to being placed on the cathode ray tube) but at the gap or opening thereof the opposed ends 60, 6| have intertting parts 62, 63 so that the effect of a solid ring is obtained. The part 63| has a cut-away portion on the inside thereof adapted to receive the narrow tongue portion 62. The protruding portions extending toward the outside of the ring such as the ridges 24 and flanges 25, 26 are removed from tongue and the interfering protruding portions extending toward the inside of the part 6| such as the flanges 22 and 4| are removed therefrom so that a smooth, almost unperceptible union is obtained.

, Figure 5 illustrates how the ring of the present invention aids in mounting the tube to the chassis of a television set. As indicated above the ring 2|) together with the protecting plate 54 may be placed upon the tube lll at an early stage of the assembling process so that the other tubes and the workers are protected from-any accidental explosion. The cable 5|] securely holds the ring 2|! and protecting plate 54 in place.

. The protected tube I!! can then be fixed on the chassis 65 of the set at any desirable time.

For example, one or more supporting blocks 13 may be provided on the chassis to receive the lower edge of the ring 2|) and properly adjust the height of theY tube with respect'to the chassis. A cable 68 having one orV both of its ends threaded as shown at 51 may then be passed around the upper part of the exterior groove 29 and then secured and tightened upon the chassis bythe nuts B9 securely hold the tube in the position desired. Although the base |2 of the tube I0 is also held by inserting it in a suitable socket secured to the chassis 63, this may be done subsequently if desired.V Although the device` has been described in connection with a cathode ray tube with a round lens it will be understood that it can also be designed to t tubes with lenses of other shapes, for example, tubes with elliptical or rectangular lenses.

It will be readily understood therefore that the present invention provides a novel mounting and protecting ring which serves to provide a secure way of mounting a metal-backed television tube together with a protecting plate to a chassis of a television set without requiring any help from the cabinet of the set for either mounting, protecting or insulating the front or lens area of the tube. The invention also provides a device for protecting people from the effects of an exploding tube that can be employed continuously from the time preceding the assembly of the tube into a set.

I claim:

l. A mounting and protecting device for a metal-backed cathode ray tube of the type having an exterior peripheral ilange adjacent the lens thereof, said device comprising a unitary tubular clamping member formed substantially entirely of insulating flexible material and having the general configuration of the said peripheral flange of the cathode ray tube but having a gap forming two interfltting ends at 1one portion thereof, a pair of exterior peripheral flanges j forming a groove therebetween adjacent one end-l of said tube adapted to receive a tighteningstrand to hold the gapped clamping member on the ange of the cathode ray tube, a first pair of interior peripheral flanges forming a first interior groove therebetween adapted to straddle the peripheral flange of the cathode ray tube, said first interior groove being opposite 'the said exterior groove, a second pair of interior flanges at the opposite end of said clamping member, said second pair of interior flanges forming a groove therebetween adapted to receive the edges of a transparent protective plate, a transparent protecting plate in the groove formed by said second pair of flanges, said rst and second pairs of interior flanges being substantially continuous when the gap in said member is held in closed position by the tightening strand, the plane of the groove formed by said second pair of interior flanges being tilted with respect to the plane of the groove formed by said rst pair of interior anges.

2. A mounting and protecting device for a metal-backed cathode ray tube of the type having an exterior peripheral flange adjacent the lens thereof, said device comprising a unitary tubular clamping member formed substantially entirely of insulating flexible material and having the general configuration of the said peripheral fdange of the cathode ray tube but having a gap forming two interiitting ends at one portion thereof, a pair of exterior peripheral flanges forming a groove therebetween adjacent one end of said tube adapted to receive a tightening strand to hold the gapped clamping member on the liange of the cathode ray tube, a first pair of interior peripheral flanges forming a rst interior groove therebetween adapted to straddle the peripheral ilange of the cathode ray tube, said first interior groove being opposite the said exterior groove, a second pair of interior iianges at the opposite end of said clamping member, said second pair of interior flanges forming a groove therebetween adapted to receive the edges of a transparent protective plate, a trans- 6 parent protecting plate in the groove formed by said second pair of flanges, said first and second pairs of interior flanges being substantially continuous when the gap in said member is held in closed position by the tightening strand, a set of interior flanges between the first and the second pairs of iianges, said set of intermediate flanges being adapted to hold a masking plate in spaced relation to the lens of the cathode ray tube when the clamping member is in place on the cathode ray tube, a masking plate in the last named set of interior flanges, the intertting ends of the clamping member, and the iirst and second pairs of interior flanges cooperating with the cathode ray tube and the protecting transparent plate to provide a dust-proof area between the lens end of the cath-ode ray tube and the transparent protecting plate.

3. The device of claim 2 in which the plane of the second groove which holds the transparent protective plate is tilted with respect to the plane of the rst groove which is adapted to straddle the ange of the cathode ray tube.

RICHARD A. FISCH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

